1. Field of Invention
The present invention relates to a liquid crystal display device and an electronic device. More particularly, the present invention relates to a technique for achieving high-contrast reflective and transmissive displays with a wide viewing angle in a transflective liquid crystal display device having reflective and transmissive structures.
2. Description of Related Art
Transflective liquid crystal display devices that adopt reflective and transmissive display modes can perform clear display with reduced power consumption even in a dark environment by switching between the reflective and transmissive display modes according to ambient brightness. As such a transflective liquid crystal display device, a liquid crystal display device has been proposed in which a liquid crystal layer is held between transmissive upper and lower substrates, a reflective film made of metal, such as aluminum, and having a light-transmitting aperture is provided on the inner side of the lower substrate, and the reflective film functions as a transflective film. In this case, in a reflective mode, external light incident from the upper substrate passes through the liquid crystal layer, is reflected by the reflective film disposed on the inner side of the lower substrate, passes through the liquid crystal layer again, and is emitted from the upper substrate for display. In a transmissive mode, light of a backlight incident from the lower substrate passes through the liquid crystal layer from the aperture of the reflective film, and is directed to the outside from the upper substrate for display. Therefore, a region of the reflective film where the aperture is formed serves as a transmissive display region, and a region of the reflective film where the aperture is not formed serves as a reflective display region. Such a display device is described, for example, in Japanese Unexamined Patent Application Publication No. 11-242226 (page 61, FIG. 1).
As another known art, a homeotropic liquid crystal display device has been proposed which improves the viewing-angle characteristic of liquid crystal, for example, in Japanese Unexamined Patent Application Publication No. 5-113561 (page 5, FIG. 1) see Patent 2).